In the world of digital design, we have a lot of different tools that make the process of prototyping really simple. But still pen and paper remain the most useful tools for UX designers.

Paper prototyping can be extremely helpful during the early-stage conceptualizing — when a team needs to explore a variety of different concepts and choose the one that will be used. The paper prototype allows quickly visualize and test various ideas.

This article is a quick guide to paper prototyping & testing for digital interfaces.